This invention relates generally to optical devices and particularly to optical switching systems.
The increasing demand for high-speed broadband communications has resulted in a rapid increase in fiber optic communications systems which require faster and more reliable components to interconnect associated optoelectronic devices of a network. These components may include devices for steering light beams through light transmissive mediums at specific angles. Currently, devices use opto-mechanical or electro-optical technology to steer light beams to a specified angle.
Opto-mechanical technology for signal channeling or steering have several disadvantages. For example, opto-mechanical devices are bulky and slow due to the mechanical scanning devices employed for optical signal distribution. In addition, degradation of mechanical components often makes these devices less reliable. Opto-mechanical devices also require complicated three-dimensional angular alignment, resulting in a low tolerance to harsh environments. Furthermore, due to optical mode mismatching, opto-mechanical devices often fail to provide low-loss coupling among devices such as laser diodes, optical modulators, waveguide splitters, single-mode optic fibers, multi-mode optic fibers, and optical detectors.
Other conventional deflection devices, such as devices including lithium niobate, are generally faster since they do not involve moving parts. Lithium niobate devices can operate even faster (e.g., switching speed in the order of microseconds) than the thermo-optic devices (e.g., switching speed in the order of milliseconds), which are generally faster devices than the opto-mechanical devices. In addition to faster speed, the absence of moving parts in lithium niobate devices results in the lithium niobate devices being more reliable. These lithium niobate devices, however, have not been incorporated into switching systems because of their polarization dependence. The lithium niobate devices deflect light beams differently depending on their polarization states, and the polarization states of the light beams in a switching system are not always consistent.
Other types of electro-optical devices that are not polarization sensitive are available. However, these electro-optical devices are also generally incompatible with the ever shrinking electronic components fabricated today. Without the ability to integrate the optical switching technology into smaller devices, laser technology may become obsolete for many current needs.
What is needed is a polarization-insensitive optical switching device that is fast enough and can be integrated into smaller devices.